LookupIconIdFromDirectory function (winuser.h)

Article
05/24/2023

Searches through icon (RT_GROUP_ICON) or cursor (RT_GROUP_CURSOR) resource data for the icon or cursor that best fits the current display device.

To specify a desired height or width, use the LookupIconIdFromDirectoryEx function. This function calls it by passing zero in the cxDesired/cyDesired parameters.

Syntax

int LookupIconIdFromDirectory(
  [in] PBYTE presbits,
  [in] BOOL  fIcon
);

Parameters

[in] presbits

Type: PBYTE

The icon or cursor directory data. Because this function does not validate the resource data, it causes a general protection (GP) fault or returns an undefined value if presbits is not pointing to valid resource data.

[in] fIcon

Type: BOOL

Indicates whether an icon or a cursor is sought. If this parameter is TRUE, the function is searching for an icon; if the parameter is FALSE, the function is searching for a cursor.

Return value

Type: int

If the function succeeds, the return value is an integer resource identifier for the icon (RT_ICON) or cursor (RT_CURSOR) that best fits the current display device.

If the function fails, the return value is zero. To get extended error information, call GetLastError.

Remarks

A resource file of type RT_GROUP_ICON (RT_GROUP_CURSOR indicates cursors) contains icon (or cursor) data in several device-dependent and device-independent formats. LookupIconIdFromDirectory searches the resource file for the icon (or cursor) that best fits the current display device and returns its integer identifier. The FindResource and FindResourceEx functions use the MAKEINTRESOURCE macro with this identifier to locate the resource in the module.

The icon directory is loaded from a resource file with resource type RT_GROUP_ICON (or RT_GROUP_CURSOR for cursors), and an integer resource name for the specific icon to be loaded. LookupIconIdFromDirectory returns an integer identifier that is the resource name of the icon that best fits the current display device.

The LoadIcon, LoadCursor, and LoadImage functions use this function to search the specified resource data for the icon or cursor that best fits the current display device.

Requirements

Requirement	Value
Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Target Platform	Windows
Header	winuser.h (include Windows.h)
Library	User32.lib
DLL	User32.dll